Propelling the movement was New York-based startup Betterment, which remains the largest independent digital advice platform.

But now these disruptors face competition of their own: traditional wealth managers have since launched their own successful digital platforms; mobile-first investing apps are drawing away young investors; and a new wave of voice-activated AI service is working its way into wealth management.

American Banker Editor-at-Large Penny Crosman spoke with Betterment CEO Jon Stein about how the robo advisor is using behavioral biology and machine learning to make his company's platform more precise and personalized.

One recently-added feature allows clients to donate appreciated shares to charities directly on the Betterment platform. In addition to getting a tax deduction, they can also skirt capital gains levies.

Betterment has sought to improve services, particularly its RIA platform. In addition to the new charity donations feature, the firm added more staff dedicated to working with RIAs and has developed a lead generation pipeline for the dozen firms in the new Betterment Advisor Network.

In his discussion, Stein also shares thoughts on the often irrational behavior of investors and the new tax bill.